1. Field of the Invention
The present invention relates to an electric power storage system.
2. Description of the Related Art
Heretofore, as an electric power storage system, there has been proposed a system including a nonaqueous electrolyte battery which has a nonaqueous electrolyte containing an ordinary temperature molten salt, a negative electrode, and a positive electrode, a temperature detection unit to detect an environmental temperature of the nonaqueous electrolyte battery, a control unit to decrease the maximum battery voltage of the nonaqueous electrolyte battery concomitant with an increase of the environmental temperature, and a control unit to control the maximum charge amount of the nonaqueous electrolyte battery to a constant value (for example, see Patent Document 1). In this electric power storage system, cycle characteristics of the nonaqueous electrolyte battery using an ordinary temperature molten salt can be improved under high temperature environment.    Patent Document 1: JP 2007-80575 A